Analysis of Vibration in Explosion-Proof Centrifugal Fans

Analysis of Vibration in Explosion-Proof Centrifugal Fans

Some users have encountered the following issue when operating explosion-proof centrifugal fans: they have repeatedly experienced severe vibration in the fans after use. As the same situation occurs even after maintenance shutdowns, bearing failure rates are high, which has a serious impact on production. So, why does this happen? Let’s examine the specific circumstances. To resolve this issue, I believe there are three possible causes. One possible reason is that the impeller of the explosion-proof centrifugal fan is heavily contaminated with dust. In some cases, dust accumulates on the blades of the explosion-proof centrifugal fan. If this condition is left unaddressed, it will worsen over time, causing the impeller to lose its dynamic balance and resulting in severe vibration of the machine. In light of this situation, we have considered the following countermeasures. Firstly, we replaced the seals on the explosion-proof centrifugal fan with contact seals. Next, we implemented leak-proofing measures and arranged for staff to carry out regular cleaning. We then utilised maintenance or shutdown periods to clean the dust from the blades, ensuring the accuracy of the explosion-proof centrifugal fan. Following these measures, the operational performance of the unit can be improved. The second reason is that the internal shaft cantilever of the unit is excessively long, and the load it bears exceeds its load-bearing capacity. To resolve this issue, appropriate adjustments must be made based on the structure and installation conditions of the explosion-proof centrifugal fan equipment, as well as the necessary on-site requirements. For example, by moving the impeller-side bearing plate approximately 100 mm along the housing, the distance between the impeller and the impeller-side bearing housing is reduced, significantly lowering the load-bearing capacity. One possible reason is that the bearings used are too small to meet the operating requirements. To resolve this, appropriate bearings that comply with the operational requirements must be selected in accordance with the structural design of the explosion-proof centrifugal fan.